MOUNTAIN VIEW — For the past six years, Google has been expanding bit by bit beyond its Mountain View headquarters. But this year, the tech titan’s plan for a massive new push into San Jose coupled with big land buys in Sunnyvale show just how big Google’s footprint may get.

If everything the tech titan has in the works comes to pass, Google could double its square footage in Silicon Valley, potentially making room for roughly another 31,000 or more employees.

The tech titan’s outposts have already popped up at sites well beyond the company’s iconic Googleplex headquarters in Mountain View.

Google and its owner, Alphabet, have cut a swath of real estate deals in San Francisco, San Bruno, Redwood City, Palo Alto, Sunnyvale — and most recently, downtown San Jose as well as significant new acquisitions in Sunnyvale.

Google’s facilities expansion mirrors the increasingly diverse enterprises beneath the Alphabet banner. As Google plants flags outside of Mountain View, some of its technology ventures are exploring frontiers well beyond its original mission of internet searches.

“The Google that exists today is not the Google of 10 years ago,” said Reed Payne, an executive vice president with Kidder Mathews. “They are in almost every line of business you can imagine.”

In 2007, Google had 16,800 employees worldwide, a company annual report shows. In 2016, Google’s team had grown to just over 72,000 workers.

On the way to San Jose

But 2017 ushered in a stunning new set of Google expansions that could tack another 8 million to 10 million square feet onto what Google owned at the end of last year.

“This is unprecedented in the history of Silicon Valley’s growth and expansion,” said Carl Guardino, president of Silicon Valley Leadership Group, which represents businesses in attempting to shape public policy. “What we see with Google is one iconic company that is willing to make a huge investment in their future and the future of Silicon Valley.”

In downtown San Jose, near the Diridon train station, Google plans a game-changing transit village consisting of 6 million to 8 million square feet of offices. About 15,000 to 20,000 Google workers — potentially as many as the company now employs in Mountain View — could occupy office complexes that would reshape San Jose’s urban core.

Meanwhile, in a Sunnyvale industrial district known as Moffett Park, Google in July bought at least 45 buildings on 13 different streets. The buildings, some 40 years old, command a combined value of $800 million and total about 2.3 million square feet. About 11,000 Google workers could be employed in those buildings, if none were altered.

Together, those two projects would roughly equal the size of what Google owned and rented in the Bay Area at the end of 2016.

Google’s first Silicon Valley foray outside of Mountain View came back in August 2011 as it leased 715,000 square feet of prime Sunnyvale offices. Yet that was only a start.

Since then, its Silicon Valley property shopping spree appears to have surpassed other corporate growth binges of recent decades.

“There has been nothing like this in my experience,” said Phil Mahoney, a Santa Clara-based vice chairman of Newmark Cornish & Carey, a commercial realty brokerage.

Google told this news organization that it is being thoughtful and intentional regarding its future growth in the Bay Area.

“We are very aware of the issues about housing, about transportation, and the impact on the community at large, and our people are part of that community,” Mark Golan, a Google vice president of real estate services for Northern California, told the San Jose City Council before it voted in June to negotiate exclusively with Google to sell 16 city-owned parcels to the search giant.

One expansion often compared with Google’s widening footprint locally is the rapid growth during the dot-com boom by Cisco Systems in north San Jose, where Cisco is headquartered.

Sizing up other tech giants

In 1996, Cisco occupied 1.4 million square feet in San Jose. In 1999, the last year in which Cisco specified square footage for local operations, the company estimated that by 2000 it would occupy 6 million square feet of offices in San Jose and nearby, according to its filings with the Securities and Exchange Commission. That is about three-fourths of what Google owned before its recent buying binge.

Cupertino-based Apple also has carried out a huge expansion effort in recent years, with deals that brought the tech giant to Sunnyvale and North San Jose for the first time. Apple’s big efforts included its new spaceship campus in Cupertino, leases in Sunnyvale and Santa Clara, and buying and leasing land and buildings in North San Jose. If Apple were to develop all the sites, its Silicon Valley offices’ and research space footprint would reach 5.58 million square feet.

Google’s recent shopping spree for office space would catapult it far past Cisco and Apple, if all the projects come to fruition.

“They are setting the tone for real estate activity and the value of commercial real estate in Silicon Valley,” said Chad Leiker, a first vice president with Kidder Mathews, a commercial realty brokerage.

In 2007, Google occupied, through leases or ownership, 2.9 million square feet of offices in Mountain View or other cities in the vicinity, including 83 acres of land, SEC files show.

By 2016, Google listed 7.9 million square feet of space that it owned in Mountain View or nearby areas, as well as 45 acres of land.

What’s more, realty agents estimate Google now rents roughly 2 million more square feet in Sunnyvale in addition to what it owns in the South Bay, for a potential total of 9.86 million square feet.

‘Enough Google to share’

Elsewhere in the Bay Area, Google in the past few years has rented or bought roughly 2.4 million square feet of office space in San Francisco, San Bruno and Redwood City.

Google also has paid $81 million to collect older research offices and land in Palo Alto.

And in Mountain View, the search giant’s efforts include proposals for new developments, property trades with LinkedIn, purchases of several small and large office buildings and other properties, and a $1.2 billion deal in 2014 to lease Moffett Field and a historic aircraft hangar.

Ultimately, Google may need numerous villages to accommodate its growth.

“There is certainly enough Google to share in the Bay Area,” Kasperzak said. “No one community could have handled all of Google.”

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